#===============================================================================
# CRC Checker
# By Jet10985 (Jet)
#===============================================================================
# This script will perform CRC file integrity checks on specified files to
# ensure there's been no alterations or corruption of original files.
# This script has: 5 customization options.
#===============================================================================
# Overwritten Methods:
# None
#-------------------------------------------------------------------------------
# Aliased methods:
# None
#===============================================================================
=begin

Make sure to turn off LOG_CRC upon release.

I recommend not putting in too many files, because it has to load the entire
file into memory in order to check it.

This is not a completely secure way of preventing alterations, it will only
ward off amateurs.
=end

module Jet
  module CRCChecker
    
    # These are the files to be CRC checked. If you want to log the crc of the
    # file first, put the name of the file as the first part, and anything
    # as the next.
    FILES = {
    
      "Game.exe" => 142291674,
      "System/RGSS301.dll" => 1982872590
      
    }
    
    # Do you want to log the crcs of the given files to a .txt file for copying?
    LOG_CRC = true
    
    # Perform CRC checks?
    CHECK_CRC = false
    
    # This is the message that appears if CRC checks fail.
    FAILURE_MESSAGE = "Integrity checks have failed, please redownload the files or ensure that all files are present."
    
    # Should the game close if CRC checks fail?
    CLOSE_UPON_FAILURE = true
    
  end
end

if Jet::CRCChecker::LOG_CRC
  file = File.new("CRC.txt", "w+")
  Jet::CRCChecker::FILES.each_key do |key|
    file.write "\"#{key}\" => #{Zlib.crc32(File.binread(key))}"
    file.write ",\n" if Jet::CRCChecker::FILES.keys.last != key
  end
  file.close
end
if Jet::CRCChecker::CHECK_CRC
  Jet::CRCChecker::FILES.each do |file, key|
    if !File.exist?(file) || Zlib.crc32(File.binread(file)) != key
      msgbox Jet::CRCChecker::FAILURE_MESSAGE
      exit if Jet::CRCChecker::CLOSE_UPON_FAILURE
    end
  end
end